Gravity chute



Dec. 4, 1928. 1,694,019 c. G. PFEIFFER GRAVI TY CHUTE Filed'OCt. 24,1927 WITNESSES UWENTO I n K BY Umrzazz a;

A T TORNE YS angles.

Patented D ec. 4, 192,8.

UNITED STATES PATENT/OFFICE;

CIIARLEs- G. PIEIEEER, or PHILADELPHIA, PENNSYLVANIA, VAssIGNoR ToSPECIALTY ENGINEERING COMPANY, or PHILADELPHIA, rENNsYLvANIA, AVCORPORATION OF PENNSYLVANIA.

Application filed October 24, 1927.

This invention relates to gravity chutes, more particularly to those ofa spiral type useful in coiiitinuously conducting granular orpnlverulentmaterials such as coal, gravel, sand, powder, etc., fromhigher to lower levels.

The aim of my invention isto provide a compact conveyor of the` abovecharacter composed of interchangeable volute sections adapted to besecured together end for end and so configured transversely as to form,when assembled, a structure which is entirely self-sustaining, i. e.capable of' maintaining its integrity without requiring either an axialcolumn or pi lars externally thereof to support it against sagging or`collapsing under load. Y

rllhe advantages accruing to my invention will bemaniii'est Jfrom thedetailed descrip-tion of the typical yembodiment shown in the drawingswhereof, Fig. I is a planview of the spiral chute.

Fig. II is, an elevation of' the same; and

Fig. III is a detail illustration showing the transverse configurationof the volute sections of which the structure is made up.

As hereindepicted, my improved spiral chute embodies a multiplicity ofinterchangeable volute sections 5-5 which are troughed to the angularconfiguration shown in Fig. III to provide the conveying channel orraceway G. The bottom 7 of' the raceway 6 is inclined somewhat to thehorizontal7 upward from its inner spiral edge at 8. The upstandng flange`9 of the trough meets the bottom 7 in a well rounded curve 10 withavoidance of sharp corners and in'ipositimi of undue restraint againstthe free `flow of the` material in the trough. Along the inner spiraledge S, each section 5 is provided with an integral drop lflange 11, fora` purpose to be later on explained. As shown in Fig. I the sections5--5 extend over a quadrant and meet end to end along radial planes atright At their ends, the sections 5 are moreover provided with integralsecuring flanges 12, 12 adapted to abut in the juncture planes andVwhich extend inward into Inergence with the drop flanges 11. As shown,the abutment flanges 12, 12 are pierced at suitable intervals forpassage of' the securing` bolts 13.

GRAVITY CHUTE.

Serial No 228,290. f-

When the several component sections 5 of the chute are assembled andsecured together In the manner explained, it will be apparent that thedrop flanges 11 )ointly constitute a `spiral stiii'ening internally of'the structure while the abutting flanges vl2, 12 serve, at the sametime, to brace it transversely. In practice a sufficient number of theVsections 5 are joined together to forni a raceway of the desiredheight, whereupon the end sections are secured to the upper and low-erlevels between which the material is to be conveyed,-no other support orscaffolding being necessary to sustain the structure against collapseunder load by virtue of the longitudinal and transverse bracing afforded`by the flanges 11, 12.

I have thus provided a spiral conveyor-` which is extremely simple inconstruction; very economical to manufacture; and easy to erect.The'structural simplicity characterist-ic of my invention is alsoconducive to. ready replacement of sections which have become badly wornafter extensive usage, so thatupkeep expenses are reduced to the veryminimum. n

Having thus described my invention, I claim: Y

1. A spiral gravity chute embodying interchangeable angularly-troughedvolute scctions adapted to be secured togetliertcnd for end, saidsections having integrally-formed depth `flanges iointlyconstituting a.spiralizcd stiflening whereby the structure is rendered self-sustainingunder load. I

2. A spiral gravity chute embodying intercl-iangeable angularly-troughedvolute sections ada'pted to be secured together end for end, saidsections having integrally formed depth flanges at their inner edgesjointly coni stituting a spiralized internal stiftening whereby thestructure is rendered self-sustaining under` load.

3. A spiral gravity chute embodying interchangeable angularly-troughedvolute sections integrally formed with end securing ilanges adapted toabut radially of the chute structure and to brace it crosswise, anddepth fianges intersecting with said securing flanges to constitutel aspiralized stiflening whereby the structure is rendered self-sustainingunder load.

1. A gravity chute embodying interchangeable angularly-troughed volutesec-.tions kwith integral end securing flanges adapted to abut radiallyof the chute Vstructure and brace it crosswiae, .as Well lal; withintegral depth flangesatwtheir innerfedges that `ninelrsaeot with theradial flanges `aforesaid and constitute a spralized internal stfening`whereby the structure is rendered self-sustaining undef load.

In testimony whereof, I have hereunto 10 signed my name at Philadelphia,Pennsyl- Vania, this 19th day of October, 1927.

Y CHARLES G. 1am IFFER`

